In algebraic geometry an imaginary curve is an algebraic curve which does not contain any real points.[1]
For example, the set of pairs of complex numbers
(x,y)
x2+y2=-1
(i,0)
( | 5i | , |
3 |
4 | |
3 |
)
In some cases, more generally, an algebraic curve with only finitely many real points is considered to be an imaginary curve. For instance, an imaginary line is a line (in a complex projective space) that contains only one real point.[2]